Foveal light exposure is increased at the time of removal of silicone oil with the potential for phototoxicity

Foveal light exposure, and therefore the potential for phototoxicity, is transiently increased at the time of removal of silicone oil. This is due to uneven macular illumination resulting from the optical vignetting effect of different silicone oil bubble sizes. The increase in foveal light exposure may be significant when the procedure is performed under bright operating microscope light on already stressed photoreceptors of an eye filled with silicon oil. The authors advocate the use of precautions, such as central shadow filter on the operating microscope light source to reduce foveal light exposure and the risk of phototoxicity at the time of removal of silicone oil.